Earthmoving vehicles, such as loaders, typically comprise two primary power paths. A first power path for powering the ground drive of the vehicle, i.e. for locomotion of the loader, and a second power path for powering the work hydraulics of the vehicle, i.e. for moving boom and/or bucket of the loader, for example. Both power paths are usually powered by the vehicle's engine.
To decrease initial and operating costs of such earthmoving vehicles, installed engine power relative to rated operating loads has been reducing in recent years. Thus, hydraulic power requirements relative to engine power have been increasing. Consequently, especially in systems utilizing torque converter powershift transmissions, conditions arise, in which the engine lugs below a minimum RPM, which is required for achieving a necessary tractive effort, as too much power is consumed by the hydraulic system. In these situations, aspired operating tasks of the construction vehicle may not be completed satisfactorily.
To address this problem, a concept is known, in which a power limiter is provided in the hydraulic power system, the power limiter limiting the power supplied to the hydraulic power system to a prescribed fixed level. In other words, in these known systems, the hydraulic power path may not consume power of the engine beyond a prescribed fixed level, so as to always leave enough engine power available for the drivetrain power path to avoid a RPM drop below a minimal acceptable value.
However, these existing systems exhibit the drawback that the hydraulic power systems have, compared to the maximum power the machine may provide, reduced hydraulic power, thereby decreasing the construction vehicle's overall productivity.